Continuous feed device for filiform bodies particularly for rotating welding machines for pipes

ABSTRACT

A device for the continuous feed of filiform bodies comprising in combination a supply spool for the material in form of wire or tape, idly mounted on a stationary apparatus, a flexible and unextendable sliding sheath containing inside said material, having one end located in stationary position near said spool, and the other end rigid with a rotation user element, and means for causing the filiform material to slide inside the sheath with a prefixed speed.

United States Patent De Santis et al.

[ Dec. 16, 1975 CONTINUOUS FEED DEVICE FOR FILIFORM BODIES PARTICULARLYFOR ROTATING WELDING MACHINES FOR PIPES Inventors: Sergio De Santis, N0.55, Via A.

Traversari; Giovanni Farello, No. 4, Via dei Tizii, both of Rome;Roberto Torrani, No. 40, Via Strada Lanzo, Borgaro Torinese Turin, allof Italy Filed: May 22, 1974 Appl. No.: 472,509

Foreign Application Priority Data May 29, 1973 Italy 50273/73 US. Cl.226/108; 226/188 Int. Cl? B65H 17/18 Field of Search 226/108, 188, 200;

[56] References Cited UNITED STATES PATENTS 2,223,005 11/1940 Kerber2l4/338 X 2,953,799 9/1960 Arnold... 3,344,305 9/1967 Ogden 226/108 XPrimary Examiner-Richard A. Schacher Attorney, Agent, or FirmYoung &Thompson [5 7] ABSTRACT A device for the continuous feed of filiformbodies comprising in combination a supply spool for the material in formof wire or tape, idly mounted on a stationary apparatus, a flexible andunextendable sliding sheath containing inside said material, having oneend located in stationary position near said spool, and the other endrigid with a rotation user element, and means for causing the filiformmaterial to slide inside the sheath with a prefixed speed.

7 Claims, 2 Drawing Figures lllllllllllllllllfll US. Patent Dec. 16,1975 CONTINUOUS FEED DEVICE FOR FILIFORM- BODIES PARTICULARLY FORROTATING WELDING MACHINES FOR PIPES The present invention-relates to.-acontinuous. feed device for filiform bodies (wires or tapes),particularly suitable for rotating welding machineslfor pipes.-

The purpose of this invention is toprovide a deviceof the related kindallowing the gradual and controlled supply of a material in form of wireor of tape from a supply stationary base, wherein is mounted thewiresupplying spool, to a user member (arrivalbase) provided with a rotarymovement for alimited numberof revolutions, having smaller size or suchas not to be able to directly receive the supply coil.

The feed of the wire must be adjustable and independent from the speedof rotation of said arrival base.

At present, the problem is solved by pushing directly the wire from thestationary base to the rotating base. The system has drawbacks asfollows:

I. The rotation of the user body determines the winding of the wirearound said body, and this generates a stress always increasing for thepushing mean, due to the friction generated by the length of the wirewhich is formed between the stationary pushing mean and the arrival baseor utilizing member which is rotating, when the number of turns, made bysaid member, increases; moreover, the turns can overlap so as to exert abraking action on one another. This phenomenon can produce at theutilization point, a reduction or even the heating of the feed.

II. If the friction does not generate anomalous situations, it is alwaysnecessary to correct the output speed of the wire from the stationarybase depending upon the speed of the rotating member in a continuous andprecise way, in order to ensure a constant feed of the material at thearrival base.

According to this invention, a device is provided comprising incombination, a feed spool for the wire idly mounted on a spindle fixedto the stationary part, a flexible and unextendable sheath, throughwhich slides said filiforrn material, said sheath having one of its endsimmovably fixed near said spool and the other end fixed to the rotatinguser element, and means for causing said filiform material to slideinside said sheath with a prefixed speed.

Also according to this invention, the two ends of said sliding sheathare wound on two pulleys, rotatable on parallel shafts; the first pulleymounted on the stationary part carries said supply spool, while thesecond pulley is rigid with the rotating user unit.

This invention will be now described with reference to the attacheddrawing showing by way of non limitative example, one preferredembodiment of the invention itself.

IN THE DRAWING:

FIG. 1 is a front view of the device, and

FIG. 2 is a side elevational view.

With reference to the drawing, the reference letter M denotes thestationary machine, whereon is mounted the rotating race pulley Pl, onwhich is in turn mounted the spool B for the wire f.

The axis of the spool can be coincident with that of the pulley P1, oras it is shown in the FIGURE, it can be displaced. The letteralreference R denotes the rotary member to which it is wanted to carry acontrolled amount of wire f in the unit of time, and on which is mountedthe arrival base for the wire itself. The body R rotates on its supportsin the direction .as shown by the arrow of FIG. 1, and it can have, ifthe case may be, limited axial movements.

In orderto solve the problem with respect to a lim ited number of turnsof the member R, the latter carries a pulley P2' aligned with the pulleyPI, and a sheath g,

flexible and' une'xtendable, of antifriction material, is provided,having one of its ends fixed to the pulley P1,

wound with a number of turns on the pulley itself, while the other endof the sheath is fixed tofthe pulley P2, at the end of a certain length,wound about the pulley itself.

Of course, the number of turns of the sheath g wound initially about thepulley P1 is related to the turns 7 which the member R must make, therotation of which is controlled by a motor W2 provided with a pinionengaged with a toothed wheel mounted on R. A spiral spring W1 mounted onthe shaft of the pulley P1 opposes the rotary clockwise movement of thepulley it- I self so as to maintain always the sheath g under tension.

On the two pulleys P1 and P2 near to the two ends of the sheath g, aremounted two little motors ml and m2 which through the pairs of rollersr1 and r2 ensure the sliding at constant speed of the wire f within thesheath motor W2, the body R rotates clockwise as shown in FIG. 1, andthe sheath g unwinds from the pulley Pl, winding on P2, loadingmeanwhile the spring WI. Simultaneously, the motors m1 and m2 ensure thefeed of the wire f according to the speed as wanted on the user element,which rotates together with the body R. When the latter has completedthe anticipated limited number of turns, the motor W2 reverses thedirection of rotation of the body R (and therefore of the pulley P2) andthe sheath g will wind again on P1 due to the action of the spring W1.

It is to be noted that due to the little friction generated by thesliding of the wire through the sheath, one of the feeding groups eitherml, r1, or m2 r2 can be dispensed with. It is possible, if the case maybe, to dispense with the pulley Pl if a sufficient space will beavailable for the sheath g which in this case will be located along avariable length arch between the pulley P2 and the machine M, having oneend fixed to the machine M near the coil B and such a length as to allowthe winding on P2 for the desired number of turns.

In the preceding specification, and in the attached drawings, referencehas been made specifically to a rotating electric welder for pipes,being however understood that the device can be applied in all caseswherein it is wanted to feed continuously and constantly a wire or atape to a body having a rotational movement, for a limited number ofturns.

The present invention has been described in one'preferred embodiment, itbeing however understood that constructive variations might bepractically adopted without departing from the scope of the presentindustrial privilege.

Having thus described the present invention, what is claimed is:

' l. A device for continuously feeding filiform bodies from a source ofsupply to a rotary user device comprising in combination first andsecond pulleys rotatably mounted on first and second shafts,respectively, a supply spool mounted on a shaft on said first pulley forrotation relative to said first pulley, a flexible and inextensiblesliding sheath having its one end fastened to said first pulley and itsother end to said second pulley and being wound on both said pulleys,said second pulley being fastened to the rotary user device, means forcausing the filiform body to slide inside the sheath at a predeterminedspeed, and means for rotating said second pulley to cause said sheath tounwind tangentially from said first pulley and to wind up tangentiallyon said second pulley.

2. A device as claimed in claim 1, in which the last named means is anelectric motor.

3. A device as claimed in claim 1, and spring means for tensioning theportion of the sheath between said first and second pulleys.

4. A device as claimed in claim 3, said spring means being carried bythe first pulley and opposing rotation of said first pulley and causingthe rewinding of the sheath when said means for rotating said pulley nolonger winds up said sheath along said second pulley.

5. A device as claimed in claim 3, said spring means comprising atorsion spring wound about said first shaft.

6. A device as claimed in claim 1, said second pulley having a radialslot for bridging two sections of pipe to be welded.

7. A device as claimed in claim 1, and means mounting said user devicefor axial movement during rotation.

1. A device for continuously feeding filiform bodies from a source ofsupply to a rOtary user device comprising in combination first andsecond pulleys rotatably mounted on first and second shafts,respectively, a supply spool mounted on a shaft on said first pulley forrotation relative to said first pulley, a flexible and inextensiblesliding sheath having its one end fastened to said first pulley and itsother end to said second pulley and being wound on both said pulleys,said second pulley being fastened to the rotary user device, means forcausing the filiform body to slide inside the sheath at a predeterminedspeed, and means for rotating said second pulley to cause said sheath tounwind tangentially from said first pulley and to wind up tangentiallyon said second pulley.
 2. A device as claimed in claim 1, in which thelast named means is an electric motor.
 3. A device as claimed in claim1, and spring means for tensioning the portion of the sheath betweensaid first and second pulleys.
 4. A device as claimed in claim 3, saidspring means being carried by the first pulley and opposing rotation ofsaid first pulley and causing the rewinding of the sheath when saidmeans for rotating said pulley no longer winds up said sheath along saidsecond pulley.
 5. A device as claimed in claim 3, said spring meanscomprising a torsion spring wound about said first shaft.
 6. A device asclaimed in claim 1, said second pulley having a radial slot for bridgingtwo sections of pipe to be welded.
 7. A device as claimed in claim 1,and means mounting said user device for axial movement during rotation.